CERN is the largest research center in the world. With almost 2,500 direct employees and more than 12,000 collaborators from all five continents, is a real city enclosed in the famous ring of 27 km long that runs between Switzerland and France about 100 m below ground level . The average age of researchers is 29 years and there is a freshness, a vitality, a desire to explore unique.
I had the opportunity to speak at length with several researchers who deal with nanostructured materials, non-destructive measures, management of the most impo-nent-architecture informs policy in the world, the GRID, invented here to manage an incredible amount of data generated during the events of proton-proton collision occurring inside the huge ring LHC (Large Hadron Collider) and which are registered through the machines incredibly sophisticated as ATLAS, CMS, Alice.
Emilio Sassone Corsi next to the machine cryogenics that lowers the internal temperature of the LHC is about 2 K
I have an exceptional guide: Professor Lucio Rossi, physicist, professor at the University of Milan and now for over twenty years at CERN as Head of “Magnets, Cryostats and Superconductors Group”.
Rossi: my role is to project leader of the High Luminosity LHC. Means generating a machine configuration that involve more power. It’s like a Ferrari rig to make it go even faster. It takes ten years to realize this project, and we are already working on five …
ESC: start from the beginning: tell me what are the superconductors?
Rossi: superconductors are of particular materials which, in certain conditions, lose their electrical resistance. So can carry current without dissipating also very intense and without heat. The conditions for this to happen, however, are really special: the material must be very cold, I intend to 2K, about -271 ° C, the temperature superfluid helium, very close to absolute 0. Begin to be superconductors that also work with the liquid nitrogen, which melts at about -200 ° C. This material is already widely used for example in the hospital for storing cells or with which it is made cryotherapy. At this temperature, however, the materials supercon-producers have not yet the right properties to be used. You have to go to -240-250 ° C in order to work well.
ESC: what superconductors do within the LHC?
Emilio Sassone Corsi during the visit to the laboratories of superconductivity Prof. Rossi
Rossi: sending a huge amount of power within the superconductor, you can make powerful magnets that can reach nearly 10 Tesla (terrestrial magnetism is about one-centomil lesimo Tesla). If we had not adopted the superconductivity for LHC, to achieve the same magnetic power we would have to build copper cables from half a meter in diameter and would have required a 1 GW nuclear power plant to power a ring that was supposed to be about 100 km long. The whole plant of cryogenics, instead, with superconductors consumes 50MW.
ESC: how this type of technology can be useful in the industrial world?
Rossi: industrial applications, there are already in the medical industry. Magnetic resonance imaging is very often based on superconductors. Many do not know that, coming into a machine for magnetic resonance imaging, is like entering a LHC, much less powerful but based on the same principles and cooled with liquid helium. Another application is the hadron therapy, a cure for a particular class of radioresistant tumors based on proton beams. There are, in Italy alone, about ten thousand people a year who should be treated with this type of treatment.
Prof. Rossi in front of a section of the tube of the LHC
The superconductors may also be used in industrial sectors, such as the transport of energy and in so-called fault current limiters, which are of current limiters when there is a fault. Today about 10% of electrical energy is dissipated during transport, only for Italy this corresponds to 2-3 nuclear power plants. With superconductors could save almost all of this energy, except for the portion of energy that must serve to keep the cold. Superconductivity is however a friend of the transport current which also has the advantage of not generating electromagnetic pollution. Especially in some countries, where the cables are inserted in the duct, have the ability to use the same channel by inserting a superconducting cable power much greater without redoing the entire duct means saves a lot.
Then there are applications for accumulated how the superconductive magnetic energy storage. We should have some big industry that wants to invest in these new technologies, even if the first applications are uneconomical.
ESC: There will never be a chance to have superconducting at room temperature?
Rossi: this is kind of a holy grail for anyone involved in superconductivity. The US has just recently invested a lot of money to research this possibility. Other researchers have predicted that, even if it were, it would be very little used. Actually, the best solution would be to use superconductivity temperature liquid nitrogen, making it clear to the industrial energy sector that is not all that hard to do. Those who work in the medical field have already understood.
Emilio Sassone Corsi in the office del Prof. Rossi
